More than a dozen workers are in quarantine after a crew member on the Premier Oil Balmoral platform tested positive for Covid-19.
The firm said the individual has been taken off the floating production vessel (FPV) and is in isolation in accordance with NHS guidance.
A total of 14 workers who came into contact with that crew member are now also in quarantine, with 11 of those onshore and three remaining on the Balmoral, Premier Oil confirmed.
A spokesman said the firm’s priority “remains the safety and welfare of our people”.
This is the latest in a series of Covid cases and outbreaks on board North Sea installations in recent weeks.
On Monday it was confirmed that an outbreak had taken place on board the CNOOC Scott platform – which the firm has not commented on – with several workers contracting the virus.
Last week production was shut down on the Ithaca Energy FPF-1 installation after three cases were confirmed, however that number had risen to 17 as of Monday.
Ithaca said it is implementing pre-mobilisation testing and moving to minimum manning, but would not restart production until it was safe to do so.
Another incident took place last week on the Apache Forties Bravo, when a pair of workers were removed after a positive case on board.
Over in Norway, at the start of the month, at least 15 workers were airlifted from the Valaris Rowan Stavanger rig after an outbreak.
These follow repeated calls from industry to government for standardised asymptomatic testing for offshore workers, who continue to deploy as key workers.
The Premier Oil Balmoral is currently in a decommissioning phase so, unlike the FPF-1, it doesn’t mean a costly shutdown to production.
Production was ceased back in October after last year’s oil price drop impacted its economics.
It also meant fields linked to the Balmoral production hub, such as the Repsol Sinopec-operated Beauly and Burghley, were ceased.
Balmoral lies around 125miles north-east of Aberdeen in the central North Sea.
It averaged 1,500 barrels of oil equivalent per day in the first half of 2019, but produced more than 190million barrels since starting up in 1986.